Table 5 Hyperparameter summaries for ten common baseline models.

From: Explainable attention-based deep learning for classification and interpretation of heart murmurs using phonocardiograms

Model

Core approach

Typical hyperparameters

1. CNN-Baseline

2–4 conv layers + FC

LR \(\approx 1\times 10^{-3}\), batch=16, dropout=0.2

2. RNN-Baseline

BiLSTM/GRU (2 layers)

LR \(\approx 5\times 10^{-4}\), seq length=100, focal(\(\gamma =1\))

3. CNN-RNN Hybrid

CNN + LSTM stack

LR \(\approx 2\times 10^{-4}\), Weighted CE

4. CRNN-Attention

CNN + LSTM + Attention

LR \(\approx 1\times 10^{-3}\), heads=4, dropout=0.2

5. TCN Model

Temporal Conv Net

LR \(\approx 1\times 10^{-3}\), kernel size=3, Weighted CE

6. RNN-Transformer

LSTM + small Transformer

LR \(\approx 5\times 10^{-4}\), 2 layers each

7. Multi-Task CNN

Shared trunk + tasks

LR \(\approx 1\times 10^{-3}\), Weighted CE + Dice loss

8. DenseNet-Style

Dense blocks + global pooling

LR \(\approx 5\times 10^{-4}\), batch=8, dropout=0.2

9. Transformer-Lite

1–2 self-attention layers

LR \(\approx 2\times 10^{-4}\), heads=2, focal(\(\gamma =2\))

10. Wavelet-CNN

Wavelet-based conv filters

LR \(\approx 1\times 10^{-3}\), Weighted CE, L2 reg